1. Field of the Invention
This invention lies in the field of the flaring of waste gases for smokeless combustion.
More particularly this invention lies in the use of steam applied in a plurality of jets at various points and in various directions, into the rising column of gas upstream of, and into the flame zone.
Still more particularly this invention has to do with a specific type of steam manifold forming the top of the flare stack with the addition of pipes and jets in various geometrical arrangements.
2. Description of the Prior Art
It has long been known that steam injected into and mixed with the column of waste gas moving to the top of the flare stack and/or the injection of jets of steam into the cylindrical wall of the rising column of gas and flame, provides help in several ways in producing smokeless combustion of the gases.
The injection of steam serves three purposes, when applied in different ways. The first way is to provide a thorough mixture of steam and gas upstream of the point of combustion. This provides the chemical components, which, in the high temperature of the flame, are chemically transformed to provide carbon monoxide and hydrogen which burn without smoke.
The second type of action performed by the steam is to provide the aspiration and injection of air which is needed for the combustion of the gas. Since the gas itself is relatively low pressure it cannot, of its own energy, aspirate the necessary combustion air, and the energy of the steam is used for that purpose.
The third action of the steam is to provide high velocity jets which cause turbulent mixing of the steam, the air and the gas, to provide the smokeless combustion.
There are separately two ways in which a smoke-prone gas can be burned smokelessly. One is to provide sufficient air, and sufficiently well mixed steam and air so that all of the carbon in the hydrocarbon gases will be completely burned, and therefore, there will be no carbon left to create a smoke.
The second way smoke-prone hydrocarbon gases and air can be turned smokelessly with steam is to provide a chemical change in the gas, by premixing steam with the gas immediately prior to combustion so that the components that are burned are not carbon and hydrogen, but are carbon moxoxide and hydrogen, which burn with invisible end products, namely, carbon dioxide and water.
Various geometrical arrangements of gas flow and steam flow have been provided in the prior art to utilize one or two of the three requirements for promoting the smokeless combustion. In this invention means are provided for utilizing all of the possible three methods of utilizing steam for creating the smokeless combustion of flare gases.